Impact of Landscape Fire Smoke Exposure on Patients With Asthma With or Without Laryngeal Hypersensitivity.

BACKGROUND: Individuals with asthma experienced severe and prolonged symptoms after the Australian 2019 to 2020 landscape fire. Many of these symptoms, such as throat irritation, occur in the upper airway. This suggests that laryngeal hypersensitivity contributes to persistent symptoms after smoke exposure. OBJECTIVE: This study examined the relationship between laryngeal hypersensitivity and symptoms, asthma control, and health impacts on individuals exposed to landscape fire smoke. METHOD: The study was a cross-sectional survey of 240 participants in asthma registries who were exposed to smoke during the 2019 to 2020 Australian fire. The survey, completed between March and May 2020, included questions about symptoms, asthma control, and health care use, as well as the Laryngeal Hypersensitivity Questionnaire. Daily concentration levels of particulate matter less than or equal to 2.5 µm in diameter were measured over the 152-day study period. RESULTS: The 49 participants with laryngeal hypersensitivity (20%) had significantly more asthma symptoms (96% vs 79%; P = .003), cough (78% vs 22%; P < .001), and throat irritation (71% vs 38%; P < .001) during the fire period compared with those without laryngeal hypersensitivity. Participants with laryngeal hypersensitivity had greater health care use (P ≤ .02), more time off work (P = .004), and a reduced capacity to participate in usual activities (P < .001) during the fire period, as well as poorer asthma control during the follow-up (P = .001). CONCLUSIONS: Laryngeal hypersensitivity is associated with persistent symptoms, reports of lower asthma control, and increased health care use in adults with asthma who were exposed to landscape fire smoke. Management of laryngeal hypersensitivity before, during, or immediately after landscape fire smoke exposure might reduce the symptom burden and health impact.

The Impact of Functional Laryngoscopy on the Diagnosis of Laryngeal Hypersensitivity Syndromes.

BACKGROUND: Chronic cough and vocal cord dysfunction are manifestations of laryngeal hypersensitivity syndrome. OBJECTIVE: The aim of the study was to determine the clinical utility of functional transnasal laryngoscopy in patients with laryngeal hypersensitivity syndromes. METHODS: This study was a prospective observational cross-sectional study design of 71 participants with laryngeal hypersensitivity syndrome referred for functional transnasal laryngoscopy. Participants had a clinical assessment with a speech pathologist after which a provisional diagnosis of chronic cough, suspected vocal cord dysfunction, suspected muscle tension dysphonia, or a combination was made. A laryngoscopy with provocation was performed and the diagnosis revised after which the provisional and revised diagnoses were compared. RESULTS: The diagnosis changed in 67% of participants after laryngoscopy. Vocal cord dysfunction was diagnosed in an additional 17 cases when not expected clinically but discounted when suspected clinically in 12 participants. Muscle tension dysphonia was diagnosed in an additional 31 cases when not suspected clinically and not confirmed when suspected in 2. CONCLUSION: This study demonstrated that conditions such as muscle tension dysphonia and vocal cord dysfunction cannot be diagnosed based on symptoms alone. In addition to diagnostic accuracy, functional laryngoscopy enhances treatment planning and provides immediate feedback regarding laryngeal movement during respiration and phonation.

Development and validation of the Newcastle laryngeal hypersensitivity questionnaire.

BACKGROUND: Laryngeal hypersensitivity may be an important component of the common disorders of laryngeal motor dysfunction including chronic refractory cough, pdoxical vocal fold movement (vocal cord dysfunction), muscle tension dysphonia, and globus pharyngeus. Patients with these conditions frequently report sensory disturbances, and an emerging concept of the 'irritable larynx' suggests common features of a sensory neuropathic dysfunction as a part of these disorders. The aim of this study was to develop a Laryngeal Hypersensitivity Questionnaire for patients with laryngeal dysfunction syndromes in order to measure the laryngeal sensory disturbance occurring in these conditions. METHODS: The 97 participants included 82 patients referred to speech pathology for behavioural management of laryngeal dysfunction and 15 healthy controls. The participants completed a 21 item self administered questionnaire regarding symptoms of abnormal laryngeal sensation. Factor analysis was conducted to examine correlations between items. Discriminant analysis and responsiveness to change were evaluated. RESULTS: The final questionnaire comprised 14 items across three domains: obstruction, pain/thermal, and irritation. The questionnaire demonstrated significant discriminant validity with a mean difference between the patients with laryngeal disorders and healthy controls of 5.5. The clinical groups with laryngeal hypersensitivity had similar abnormal scores. Furthermore the Newcastle Laryngeal Hypersensitivity Questionnaire (LHQ) showed improvement following behavioural speech pathology intervention with a mean reduction in LHQ score of 2.3. CONCLUSION: The Newcastle Laryngeal Hypersensitivity Questionnaire is a simple, non-invasive tool to measure laryngeal pesthesia in patients with laryngeal conditions such as chronic cough, pdoxical vocal fold movement (vocal cord dysfunction), muscle tension dysphonia, and globus pharyngeus. It can successfully differentiate patients from healthy controls and measure change following intervention. It is a promising tool for use in clinical research and practice.

Laryngeal sensory dysfunction in laryngeal hypersensitivity syndrome.

BACKGROUND AND OBJECTIVE: Diseases associated with laryngeal dysfunction include chronic refractory cough (CRC), paradoxical vocal fold movement (PVFM), muscle tension dysphonia (MTD) and globus pharyngeus. We hypothesized the presence of a common sensory laryngeal dysfunction, the 'laryngeal hypersensitivity' syndrome, in these conditions. The aim of the study was to compare symptoms and sensory function in patients with CRC, PVFM, MTD and globus. METHODS: The 103 participants included healthy controls (n = 13) and four case groups: CRC (n = 33), PVFM (n = 28), globus pharyngeus (n = 11) and MTD (n = 18). Participants completed self-report questionnaires: Symptom Frequency and Severity Scale, Voice Handicap Index and the Laryngeal Paraesthesia Questionnaire; and quantitative sensory testing: capsaicin cough reflex sensitivity, hypertonic saline challenge, the timed swallow test, acoustic voice testing, cough frequency monitor and a voice stress test. RESULTS: All case groups reported a high-symptom burden in comparison to controls. The case groups showed a similar pattern of symptoms, with impairment in each of the cough, respiration, vocal and upper airway symptom domains. Objective testing revealed significant sensory impairment in the case groups compared to controls and also showed an overlap in sensory dysfunction between the four case groups. Furthermore, there was cross-sensory stimulation of symptoms whereby stimulation of a particular response resulted in symptoms in another domain. CONCLUSIONS: These discrete clinical laryngeal syndromes display considerable overlap in their clinical features and a common sensory dysfunction, supporting the 'laryngeal hypersensitivity' hypothesis. Reconceptualizing functional laryngeal disorders as a form of laryngeal hypersensitivity syndrome provides an alternative approach to management of these perplexing conditions.

Auditory-perceptual voice characteristics in pre-operative patients undergoing thyroid or parathyroid surgery.

OBJECTIVES: To systematically evaluate auditory perceptual voice characteristics in people with thyroid disease prior to undergoing thyroid surgery. PATIENTS AND METHODS: This study examined the auditory perceptual voice characteristics of 96 individuals with thyroid disease. Participants were categorised by type of thyroid disease (i.e. multinodular goitre, thyroid cancer, thyroid nodule, toxicity or parathyroidism) and by status of compression (i.e. compression versus no compression). Auditory perceptual voice ratings were made on samples of connected speech by using the Perceptual Voice Profile. RESULTS: A high prevalence of participants had deviant auditory perceptual voice features; however, the majority of these abnormalities were slight to mild in severity and only 8% of participants had a clinically significant auditory perceptual abnormality. There was no significant difference in features between diagnostic categories, and only high pitch was rated as more significantly deviant in patients without compression versus those with compression. CONCLUSIONS: This study supports the need for auditory-perceptual ratings to be included as part of pre-operative multidimensional assessment of voice in patients with thyroid disease.